Lubricating oil composition for protection of silver bearings in medium speed diesel engines

Abstract

Provided herein is a medium speed diesel engine crankcase lubricating oil composition comprising: (a) major amount of an oil of lubricating viscosity; and (b) 0.1 to 5.0 weight percent of a silver lubricity additive comprising: (iv) an alkoxylated fatty amine or salt thereof; (v) an alkoxylated fatty diamine or salt thereof; or (vi) mixtures of (i) and (ii) above. Also provided is a method for reducing silver bearing wear and friction in medium speed diesel engines comprising lubricating said engine with said lubricating oil composition.

What is claimed is: 
     
         1 . A medium speed diesel engine crankcase lubricating oil composition comprising:
 (a) a major amount of an oil of lubricating viscosity; and   (b) 0.1 to 5.0 weight percent of a silver lubricity additive comprising:
 (i) an alkoxylated fatty amine or salt thereof; 
 (ii) an alkoxylated fatty diamine or salt thereof; or 
 (iii) mixtures of (i) and (ii) above. 
   
     
     
         2 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty amine is of Formula 1: 
       
         
           
           
               
               
           
         
         wherein R 1  is an aliphatic fatty acid chain ranging from C8 to C24; R 2  is independently hydrogen or alkyl of C1 to C8; and wherein x and y independently are each at least 1 and x+y≦50; and 
       
       wherein the alkoxylated fatty diamine is of Formula 2: 
       
         
           
           
               
               
           
         
         wherein R 3  is an aliphatic fatty acid chain ranging from C8 to C24; each R 4  is independently hydrogen or alkyl of C1 to C8; and R 5  is a divalent alkylene of C1 to C8; wherein a+b+c independently are each at least 1 and a+b+c≦50. 
       
     
     
         3 . The lubricating oil composition of  claim 2 , wherein x and y independently are each at least 1 and x+y≦20. 
     
     
         4 . The lubricating oil composition of  claim 2 , wherein a, b and c independently are each at least 1 and a+b+c≦30. 
     
     
         5 . The lubricating oil composition of  claim 2 , wherein x and y independently are each at least 1 and x+y≦40. 
     
     
         6 . The lubricating oil composition of  claim 2 , wherein x and y independently are each at least 1 and x+y≦30. 
     
     
         7 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty amine salt is of Formula 3: 
       
         
           
           
               
               
           
         
         wherein R 1  is an aliphatic fatty acid chain ranging from C8 to C24; R 2  is independently hydrogen or alkyl of C1 to C8; wherein x and y independently are each at least 1 and x+y≦50; and wherein Z is an anion of an organic or an inorganic acid; and 
         wherein the alkoxylated fatty diamine salt is of Formula 4: 
       
       
         
           
           
               
               
           
         
         wherein R 3  is an aliphatic fatty acid chain ranging from C8 to C24; each R 4  is independently hydrogen or alkyl of C1 to C8; and R 5  is a divalent alkylene of C1 to C8; wherein a+b+c independently are each at least 1 and a+b+c≦50; and wherein Z is an anion of an organic or an inorganic acid. 
       
     
     
         8 . The lubricating oil composition of  claim 7 , wherein x and y independently are each at least 1 and x+y≦20. 
     
     
         9 . The lubricating oil composition of  claim 7 , wherein a+b+c independently are each at least 1 and a+b+c≦30. 
     
     
         10 . The lubricating oil composition of  claim 7 , wherein Z is selected from the group comprising: phosphate, phosphite, dithiophosphate, sulfate, sulfonate, carbonate, and anions from carboxylic acid and fatty acid. 
     
     
         11 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty amine is selected from the group comprising: propoxylated monoamine, butoxylated monoamine, alkoxylated alkyl diisopropanolamine, ethoxylated monoamines such as ethoxylated octadecylamine, ethoxylated cocoalkylamines, ethoxylated oleylamines, diethoxylated oleylamine, ethoxylated soyaalkylamines, and ethoxylated tallowalkylamines. 
     
     
         12 . The lubricating oil composition of  claim 11 , wherein the alkoxylated fatty amine is diethoxylated oleylamine. 
     
     
         13 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty diamine is selected from the group comprising ethoxylated diamines such as tris(2-hydroxyethyl)-N-tallowalkyl-1,3-diamine propane commonly known as Ethoduomeen T/13, Ethoduomeen T/20 and Ethoduomeen T/25. 
     
     
         14 . The lubricating oil composition of  claim 13 , wherein the alkoxylated fatty diamine is tris(2-hydroxyethyl)-N-tallowalkyl-1,3-diamine propane. 
     
     
         15 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty salt is diethoxylated oleylammonium bis(2-ethylhexyl)phosphate. 
     
     
         16 . The lubricating oil composition of  claim 1 , wherein the silver lubricity additive is an organic or inorganic alkoxylated fatty amine or diamine salt selected from the group comprising: phosphate, phosphite, dithiophosphate, sulfate, sulfonate, carbonate, and anions from carboxylic acids and fatty acids. 
     
     
         17 . The lubricating oil composition of  claim 16 , wherein the alkoxylated fatty amine salt group is an alkyl acid phosphate group. 
     
     
         18 . The lubricating oil composition of  claim 17 , wherein the alkyl acid phosphate group is di-alkyl monohydrogen phosphate or mono-alky di-hydrogen phosphates according to formula 5 and 6 below: 
       
         
           
           
               
               
           
         
         wherein R 6 , R 7  and R 8  are independently linear chain, branched chain alkyl or alkylated aromatics having from about 3 to about 40 carbon atoms. 
       
     
     
         19 . The lubricating oil composition of  claim 18 , wherein the alkyl acid phosphate group is selected from the group comprising:
 di-2-ethylhexyl hydrogen phosphate, di-hexyl hydrogen phosphate, propyl di-hydrogen phosphates, di-propyl hydrogen phosphates, butyl di-hydrogen phosphates, butyl di-hydrogen phosphates, di-pentyl hydrogen phosphates, hexy di-hydrogen phosphates, di-hexyl hydrogen phosphates, heptyl di-hydrogen phosphates, di-hepty hydrogen phosphates, octyl di-hydrogen phosphates, di-octyl hydrogen phosphates, decyl di-hydrogen phosphate, di-decyl hydrogen phosphates, decyl di hydrogen phosphates, di-decyl hydrogen phosphate and the like.   
     
     
         20 . The lubricating oil composition of  claim 19 , wherein the alkyl acid phosphate group is di-2-ethylhexyl hydrogen phosphate. 
     
     
         21 . The lubricating oil composition of  claim 1 , wherein the alkoxylated fatty amine or alkoxylated fatty diamine contain a saturated or unsaturated C 12 -C 24  alkyl radical which is branched or straight chain. 
     
     
         22 . The lubricating oil composition of  claim 21 , wherein the saturated or unsaturated alkyl radical contains 14 to 20 carbon atoms. 
     
     
         23 . The lubricating oil composition of  claim 22 , wherein the saturated or unsaturated alkyl radical contains 16 to 18 carbon atoms. 
     
     
         24 . The lubricating oil composition of  claim 1 , wherein the silver lubricity additive is present at 0.20 to 4 weight percent. 
     
     
         25 . The lubricating oil composition of  claim 24 , wherein the silver lubricity additive is present at 0.20 to 3 weight percent. 
     
     
         26 . The lubricating oil composition of  claim 25 , wherein the silver lubricity additive is present at 0.20 to 2 weight percent. 
     
     
         27 . The lubricating oil composition of  claim 26 , wherein the silver lubricity additive is present at 0.20 to 1 weight percent. 
     
     
         28 . The lubricating oil composition of  claim 1 , wherein the medium speed diesel engine is selected from the group comprising railroad locomotive, marine tugboat and stationary power engines. 
     
     
         29 . The lubricating oil composition of  claim 13 , wherein the medium speed diesel engine is a railroad locomotive engine. 
     
     
         30 . The lubricating oil composition of  claim 13 , wherein the medium speed diesel engine is a marine tugboat engine. 
     
     
         31 . The lubricating oil composition of  claim 13 , wherein medium speed diesel engine is a stationary power engine. 
     
     
         32 . A method for reducing silver bearing wear and friction in a medium speed diesel engine comprising lubricating said engine with a lubricating oil composition comprising:
 (a) a major amount of an oil of lubricating viscosity; and   (b) 0.1 to 5.0 weight percent of a silver lubricity additive comprising:
 (i) an alkoxylated fatty amine or salt thereof; 
 (ii) an alkoxylated fatty diamine or salt thereof; or 
 (iii) mixtures of (i) and (ii) above.